. Radiography and radio-therapeutics . er for most are photographed togetheron one whole plate. A special table has beendesigned to facilitate the trac-ings of the negatives. Figs. 282, 283, and 284 illustrate the yw,. 281.—Showing diagram ilrawn in hy means of thegeneral plan of the table ; the pantograph, particulars of case, and description of the- , . , , . conditions found. table top IS drawn to scale, as is also the elevation plan, and all the necessary dimensions are figured, so that anv one can con- ■ ■ - struct it from the plan. On the right-hand sideof the table top a
. Radiography and radio-therapeutics . er for most are photographed togetheron one whole plate. A special table has beendesigned to facilitate the trac-ings of the negatives. Figs. 282, 283, and 284 illustrate the yw,. 281.—Showing diagram ilrawn in hy means of thegeneral plan of the table ; the pantograph, particulars of case, and description of the- , . , , . conditions found. table top IS drawn to scale, as is also the elevation plan, and all the necessary dimensions are figured, so that anv one can con- ■ ■ - struct it from the plan. On the right-hand sideof the table top a largehole is cut; into this apiece of thin plate glassis accurately fitted, itssurface being flush withthe table top. The nega-tive to be traced isplaced film down uponthe plate glass, so thatthe spine correspondswith the vertical threadV, which is stretchedbelow the glass. Beneaththe table is a board R,covered with white reflected light is ob-tained from a lamp L, con-trolled by the switch reflector is hinged to. Fig. 282.—Showing general construction of table. 334 EADIOGRAPHY the table rail, aud the angle adjusted by a string or fine metal card, similar to Fig. 281, on which the tracing is made, is slipped underthe heads of drawing pins at the corners. Once the relative position ofnegative and card have been found the drawing pins need not be removed,they form fixed points for controlling the position of all the cards pantograph works from the fixed point P. This consists of a brass pinlet into a brass plate, and forms a convenient point from which the panto-graph may be worked. The plate is flush with the table top. The pincan therefore be withdrawn at any time, leaving the table top clear forother work.
Size: 1530px × 1632px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookauthorknoxrobert18681928, bookcentury1900, bookdecade1910
